According to a study posted on Medical Xpress, hot flashes could potentially be triggered by a group of brain cells known as KNDy neurons which are located in the hypothalamus, a part of brain which functions as a switchboard between the central nervous system and hormone signals.
Dr. Naomi Rance, professor of pathology at the UA College of Medicine, and her team found the mechanism of hot flashes, which can lead to better treatments in the future. This affects many people and not just women.
"Although the KNDy neurons are a very small population of cells, our research reveals that they play extremely important roles in how the body controls its energy resources, reproduction and temperature," said Melinda Mittelman-Smith, who led the study as part of her doctoral thesis, in a report from Medical Xpress. "They are true multitaskers."
The study was conducted to chart KNDy neurons in rats, and was found that the tail skin temperature was lower in the rats whose KNDy neurons were inactivated, according to Medical Xpress. It was discovered that the neurons controlled the process of widening of blood vessels resulting in increased blood flow through the skin, known as vasolidation.
"The hallmark of hot flushes is vasodilation," said Rance, who also is a neuropathologist at The University of Arizona Medical Center, reported Medical Xpress. "When you flush, your skin gets hot and you can see the redness of the skin. It is an attempt of the body to get rid of heat, just like sweating. Except that if you were to measure core temperature at that point, you would find it is not even elevated."
The results do not directly apply in helping individuals, Rance said, but marks the significant start.
"Obviously we can't do these studies in women, and only if we understand the mechanism is there a chance of developing therapies. All that is known so far is that dwindling estrogen levels have something to do with it but anything after that is a black box," she said.
Estrogen-replacement therapy is the only effective way for the treatment of hot flashes, but further study could help researchers learn more about the cause of hot flashes can develop "a better, more targeted therapy," Rance said, according to Medical Xpress.
Rance and her team explained why they measured the rat's tail skin temperature. "Rats regulate heat dissipation with their tail because the rest is covered by fur. In rats without ovaries, the lack of estrogen causes vasodilation, which we can measure as increased tail skin temperature." The team then compared the tail skin temperatures of rats with intact KNDy neurons to inactivated KNDy neurons and found that the tail skin temperatures fluctuated throughout the day and night, according to Medical Xpress.
"The rats didn't seem unhappy at all," she said. "You'd think they'd be curling up and shivering, but no. There was no difference in the core temperature, so they weren't internally cold. We did all the activity measurements and found them to be completely normal. We couldn't tell a difference other than lower vasodilatation."
The researchers said the KNDy neurons are not responsible for managing body temperature but are critically important for normal thermoregulation.
"I wouldn't say we solved the problem, but we have a good clue about what could be causing the flushes," she said.
These finding are published in the Proceedings of the National Academy of Sciences.
